高效解磷细菌的筛选及其对玉米苗期生长的促进作用

采用改良后的PVK平板，从石灰性土壤上长势良好的野生植物根表分离到44株解磷细菌，通过NBRIP液体摇瓶实验，培养7 d后发现：K₃菌株培养液中全磷浓度高达643.2 μg·ml^-1，可溶性磷为584.8 μg·ml^-1，约有12.9%的磷酸三钙被溶解出来，为对照(CK)的10.5倍；K₉菌株培养液的全磷浓度为608.5 μg·ml^-1，可溶性磷浓度为606.4 μg·ml^-1.盆栽试验的结果表明：接种解磷细菌的处理玉米株高、茎粗和干质量显著高于CK；将有机肥作为载体和解磷细菌一同混合施入土壤的处理，玉米苗干质量较单施解磷菌显著增加.经初步鉴定, K₃、K₉为假单胞菌属.

High effective phosphate-solubilizing bacteria: Their isolation and promoting effect on corn seedling growth

By using modified PVK plate method, 44 strains of phosphate-solubilizing bacteria (PSB) were isolated from the root surface of wild plants growing well in calcareous soil. After 7-day incubation in a liquid medium NBRIP, the total P in the cultures of strains K3 and K9 reached 643.2 microg x ml(-1) and 608.5 microg x ml(-1), and soluble P was 584.8 microg x ml(-1) and 606.4 microg x ml(-1), respectively. About 12.9% of tricalcium phosphate was dissolved, being 9.5 times higher than CK. Pot experiment showed that the plant height, stem diameter, and dry mass of corn seedling were significantly higher in PSB treatments than in CK. Applying PSB agent with manure as a carrier could significantly increase the seedling's dry mass, in comparing with applying PSB agent alone. The strains K3 and K9 were identified as Pseudomonas.